Introduction Model Software Benefits

Software Modeling of Liquids & Gases

IntroductionGeneral StructureAspects ModeledSpecific IssuesMalfunctionsDesign Process

General Structure

An important aspect of this type of software is modularity, thus enabling new models to be produced quickly and reliably, and existing models to be readily updated if required. All models share basic aspects such as fluid flow, heat flow, control logic and the modular structure takes advantage of these common aspects.

A crucial feature is that the models are largely table-driven, meaning that most of the modifications on an existing model, and all the fine tuning, can be done on-line, since all parameters are accessible.

From the modeler's point of view there are thus four basic issues to address when developing new models (given a library of existing modules already developed for previous models):

Initialization
The tables driving the models have to be initialized. This will be done only for a new model. The table contents reflect physical data (tank volumes, pump ratings, valve sizes, network structures) which will "never" change.

Linking
The appropriate existing modules have to be identified, modified if necessary (or new ones produced), and linked together to produce a model.

Specific Aspects
Model-specific aspects (such as control logic, which is usually different for each application) have to be modeled specifically.

Real Data Comparison
Where real performance data exist, the model can be tuned to reflect these.